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demography of

Djibouti

...is determined by clan-family membership. More than half the Somali belong to the Issa, whose numbers exceed those of the Afar; the remaining Somali are predominately members of the Gadaboursi and
Isaaq clans that migrated from northern Somalia during the 20th century to work on the construction of the Djibouti–Addis Ababa railway and Djibouti city’s port expansion.

Somalia

...of northeastern Somalia, the Ogaden, and the border region between Somalia and Kenya; the Hawiye, chiefly inhabiting the area on both sides of the middle Shabeelle and south-central Somalia; and the
Isaaq, who live in the central and western parts of northern Somalia. In addition, there are the Dir, living in the northwestern corner of the country but also dispersed throughout southern Somalia,...

history of Somalia

...from Arabia to settle in the northeastern corner of the Somali peninsula in the 11th century. This was followed, perhaps two centuries later, by the settlement of Sheikh Isaq, founder of the
Isaaq Somali. As the Daarood and
Isaaq clans grew in numbers and territory in the northeast, they began to vie with their Oromo neighbours, thus creating a general thrust toward the southwest. By the...

...groups: the Somali Salvation Democratic Front (SSDF), drawing its main support from the Majeerteen clan of the Mudug region in central Somalia, and the Somali National Movement (SNM), based on the
Isaaq clan of the northern regions. Formed in 1982, both organizations undertook guerrilla operations from bases in Ethiopia. These pressures, in addition to pressure from Somalia’s Western backers,...